Extruded ceramic log transfer system

ABSTRACT

An apparatus for orienting section of a plasticized ceramic extrudate includes a marking assembly for applying an orientation reference mark to a plasticized ceramic extrudate exiting an extrusion die onto an extrudate support, and at least one extrudate-contacting deformable roller having an axis of rotation, wherein the axis of rotation is pivotable with respect to a movement of the extrudate exiting an extrusion die, and wherein the roller is adapted to contact the extrudate and correct a corkscrew deformation of the extrudate exiting the extrusion die. The apparatus also includes at least one extrudate-contacting orientation control member for correcting the orientation of a cut section of the extrudate on the extrudate support in response to a misalignment of the reference mark. The apparatus further includes at least one gripping member adapted to laterally transfer the cut section of the extrudate along a linear path with respect to the extrudate support while preventing any orientation change of the cut section of the extrudate support, and a visual inspection apparatus adapted to confirm the orientation of the cut section of the extrudate on extrudate support.

BACKGROUND OF THE INVENTION

The invention relates to an extruded ceramic log transfer system, andmore specifically to an automated extruded ceramic log transfer system.

Extruded logs or extrudates of ceramic are used in a wide variety ofapplications, such as substrates for automotive exhaust catalyticconverters, particulate traps within diesel engines, chemical filtrationprocesses, and the like. The manufacturing process for these extrudatestypically include the transfer of the wet log along a manufacturing lineor cell subsequent to being extruded from an associated extrusion die.

Heretofore, this transfer is typically conducted via a manual processthat requires an operator to physically touch the ceramic extrudateeither hand- and/or a utensil. The forces as exerted by the operatoronto the ceramic extrudate when touching the same are variable in natureand differ from operator to operator and part to part, thereby resultingin a non-uniform deformation of the extrudate during processing. As inmany industries, the dimensional requirements for these extrudatescontinue to be narrowed, thereby making the manual deformation of thesefilters unacceptable. Specifically, the tolerances associated with thealignment of the internal cells of many ceramic extrudates must beclosely held to assure proper shape and fluid flow therethrough.Further, the demand for cylindrically-shaped filter bodies has increaseddramatically in recent years. The cylindrical shape of these filtersmakes it inherently difficult to manually handle the same. Moreover,cycle times associated with the manufacturing process are significantlyeffected by the non-uniform manual feeding process. Another problemassociated with manual manipulation of the extrudates includes thevariability of locating the ceramic extrudates in a position to be firedor cured without allowing deformation of the associate cells due togravitational forces.

A manufacturing process is therefore desired that removes theinconsistencies associated with manual feeding of an extruded ceramiclog or extrudate, including reducing the deformation of the extrudateduring the forming process, increasing the precision of alignment of theextrudate prior to curing and/or firing, and decreasing cycle time.

SUMMARY OF THE INVENTION

One aspect of the present invention is to provide an apparatus fororienting sections of a plasticized ceramic extrudate that includes amarking assembly for applying an orientation reference mark to aplasticized ceramic extrudate exiting an extrusion die onto an extrudatesupport, and at least one extrudate-contacting orientation controlmember for correcting the orientation of the cut section of theextrudate on the extrudate support in response to misalignment of thereference mark. The apparatus also includes at least one gripping memberadapted to laterally transfer the cut section of the extrudate along alinear path with respect to the extrudate support while preventing anyorientation change of the cut section of the extrudate support. Theapparatus further includes a visual inspection apparatus adapted toconfirm the orientation of the cut section of the extrudate on theextrudate support.

Another aspect of the present invention is to provide a method fororienting sections of a plasticized ceramic extrudate that includesapplying a reference mark to a plasticized extrudate as the extrudateexits the extrusion die into an extrudate support, and supporting theextrudate on the extrudate support. The method also includes cutting theextrudate to form a cut section of the extrudate, and correcting theorientation of the cut section of the extrudate in response to areference mark misalignment and as the extrudate is supported by theextrudate support. The method further includes transferring the cutsection of the extrudate along a length of the extrudate support whilepreventing any orientation change of the cut section, and visuallyinspecting the orientation of the cut section of the extrudate.

Yet another aspect of the present invention is to provide an apparatusfor orienting sections of a plasticized ceramic extrudate that includesa marking assembly for applying an orientation reference mark to aplasticized ceramic extrudate exiting an extrusion die onto theextrudate support, and at least one extrudate-contacting orientationcontrol member for correcting the orientation of the cut section of theextrudate on the extrudate support in response to a misalignment of thereference mark.

Still another aspect of the present invention is to provide an apparatusfor correcting deformation of a plasticized ceramic extrudate exiting anextrusion die that includes a support frame, and at least oneextrudate-contacting deformable roller operably coupled to support frameand having an axis of rotation, wherein the axis of rotation ispivotable with respect to a movement and extrudate exiting an extrusiondie, and wherein the roller is adapted to contact the extrudate andcorrect a corkscrew deformation of the extrudate exiting the extrusiondie.

The present inventive methods and associated apparatus disclosed hereinare highly consistent and repeatable, remove the inconsistenciesassociated with prior art methods and apparatus, reduce the deformationof the associated ceramic extrudates as manufactured via prior artsystems and methods, increase the precision of alignment prior to curingand/or firing the associated extrudates, reduce manufacturing cycletimes, and are particularly well adapted for the proposed use.

These and other advantages of the invention will be further understoodand appreciated by those skilled in the art by reference to thefollowing written specification, claims and appended drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an extruded ceramic log transfer systemembodying the present invention;

FIG. 2 is a top plan schematic view of the transfer system;

FIG. 3A is a partially schematic perspective view of a continuous inkjet system of the transfer system;

FIG. 3B is an extrudate including ink markings applied by the ink jetsystem;

FIG. 4 is a perspective top view of a corkscrew correction roller systemof the transfer system;

FIG. 5 is a partially schematic perspective view of an automatic logalignment system of the transfer system;

FIG. 6 is a partially schematic perspective view of an automatic graband drag system of the transfer system; and

FIG. 7 is a partially schematic top perspective view of a log alignmentcamera system of the transfer system.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

For purposes of description herein, the terms “upper,” “lower,” “right,”“left,” “rear,” “front,” “vertical,” “horizontal,” and derivativesthereof shall relate to the invention as oriented in FIGS. 1 and 2.However, it is to be understood that the invention may assume variousalternative orientations and step sequences, except where expresslyspecified to the contrary. It is also to be understood that the specificdevices and processes illustrated in the attached drawings, anddescribed in the following specification are exemplary embodiments ofthe inventive concepts defined in the appended claims. Hence, specificdimensions and other physical characteristics relating to theembodiments disclosed herein are not to be considered as limiting,unless the claims expressly state otherwise.

The reference numeral 10 (FIGS. 1 and 2) generally designates anextruded ceramic log transfer system embodying the present invention. Inthe illustrated example, the transfer system 10 includes an extrusionapparatus 12 having an extrusion die 13 adapted to form a ceramicextrudate 14, and a continuous ink jet system or marking assembly 15 forcontinuously marking the extrudate 14 as it is extruded from theextrusion die 13 onto an extrudate support 25. The transfer system 10also includes a corkscrew correction roller system or corkscrewcorrection assembly 16 that corrects a corkscrew deformation of theextrudate 14 as it is extruded through the extrusion die 13. Thetransfer system 10 further includes a wet saw assembly 17 that cuts aportion or segment 18 from the extrudate 14. An automatic log alignmentsystem or orientation control system 19 is used to properly align theextrudate segment 18 in reference to a reference mark as provided by theinkjet system 15, as described below. A grab and drag system 20 isutilized to move the extrudate segment 18 in a linear path within thetransfer system 10 and repositions the segment 18 from the extrudatesupport 25 onto a dryer tray 21 for movement along a conveyor system 22.A wet log alignment camera system or visual inspection system 23 is thenutilized to monitor the alignment of the segment 18 as it rests on theassociated dryer tray 21.

The inkjet system 15 (FIG. 3) includes an inkjet print head 26 forprinting an orientation reference mark 28 (FIG. 3B) on the extrudate 14as the extrudate 14 is extruded from the extrusion die 13. The printhead 26 may further be used to provide a date stamp 30 (or otherinformation for traceability) on the extrudate 14 for the purpose ofquality tracking and control. The print head 26 is in fluidcommunication with an ink reservoir 32. An optical reader or photo eye34 is utilized to detect the presence of the extrudate 14. The printhead 26 and the optical reader 34 are in operable communication with acontroller 36 that receives the signals from the optical reader 34 andcontrols the print head 26 in response thereto. It should be noted thatprint head 26 is located as close as physically possible to theextrusion die 13 so as to accurately mark the extrudate 14 as it isextruded from the extrusion die 13 prior to deformation of the extrudate14, such as the corkscrewing effect caused by the extrusion process.Preferably, the ink jet system 15 includes a Linx 4800 continuous inkjetunit as available from Diagraph of St. Charles, Mo., however, otherinking systems may be utilized.

The corkscrew correction roller system 16 (FIG. 4) includes a frame 38extending upwardly from the extrudate support 25, and a verticallyadjustable support assembly 40. The vertical location of the supportassembly 40 with respect to the extrudate support 25 is adjusted via adial 42 operably connected to a threaded adjustment rod 44, that is inturn threadably coupled with the support assembly 40. A pair ofelastically deformable rollers 46 are supported below the supportassembly 40 via a pair of C-shaped hanging brackets 48. Each roller 46is cylindrically shaped defining a pivot axis 50, and are preferablyconstructed of a material that will not cause deformation of an outersurface of the extrudate 14 while in contact therewith. The hangingbrackets 48 are operably coupled to the support assembly 40 such thatthe rotation of an adjustment handle 52 causes the pivot axis 50 of therollers 46 to move out of perpendicular alignment with a centroidal axis54 of the extrudate 14.

In operation, the extrusion die 13 is known to cause a corkscrewdeformation of the extrudate 14 as the extrudate 14 is extrudedtherefrom. As the extrudate 14 moves along the extrudate support 25 in adirection as represented and indicated by arrow 56, the corkscrewdeformation of the extrudate 14 as caused by the extrusion die 13 iscorrected by contacting the rollers 46 with an outer surface of theextrudate 14. Specifically, the pivot axis 50 of each roller 46 isadjusted via the adjustment handle 52 such that the rollers impinge onthe outer surface of the extrudate 14 in a direction that causes acounter rotation to the corkscrew deformation. In other words, lookingdown vertically from above the extrudate 14, if there is no corkscrew tobe corrected for, the pivot axis 50 is perpendicular to the axis 54 ofextrudate 14. If, on the other hand, there is corkscrew present in theextrudate 14, the pivot axis 50 is askew from perpendicular to the axis54 of extrudate 14, to thereby cause counter rotation to the corkscrewdeformation. It should be noted that the correction of the corkscrewdeformation is conducted prior to the extrudate 14 being cut into thesegments 18, thereby eliminating the requirement to support a freeextrudate segment 18 while attempting to correct for the corkscrewdeformation.

A laser encoder 58 is utilized to monitor the extrusion velocity, i.e.,the velocity that the extrudate 14 is extruded from the extrusionapparatus 12. The velocities as read by the laser encoder 58 are relayedto a controller 59, that may be included within a central controlsystem, where the velocity readings are utilized to time and sequencethe grab and drag system 20 as well as other subsequently completedsteps and procedures. A wet saw 17 is then utilized to cut the extrudatesegments 18 from the continuous extrudate 14. As wet saws are generallywell known in the art, a detailed description of the same is notprovided.

The automatic log alignment system 19 (FIG. 5) includes an air bearing60 having a bearing surface 62 upon which the extrudate segment 18 isfree to float once cut from the continuous extrudate 14. The bearingsurface 62 includes a plurality of air jet apertures through which acontinuous supply of forced air is exerted therethrough to floatinglysupport the segment 18 thereon once the segment 18 is cut from thecontinuous extrudate 14. The alignment system 19 also includes a camerasystem that takes an optical reading of the reference mark 28 andcommunicates the same with a controller 68, which may be included withina central control system. The controller 68 is in operable communicationwith an alignment assembly that includes a servo motor 72 operablycoupled with a gear box 74, that is in turn coupled with a supportassembly 76 that pivotally supports an elastically deformable roller 78such that the pivotal axis 80 of the roller 78 can be pivoted about avertical axis 82. The roller 78 is preferably constructed of a materialthat does not cause deformation of the segment 18 when in contracttherewith, such as a foam.

In operation, the camera system 36 monitors the position of thereference mark 28 and communicates those readings with the controller 68where the position of the reference mark 28 is compared with apredetermined reference point. Should misalignment occur, the controller68 operates the servo motor 72 to pivot the support assembly 76 aboutthe axis 82, thereby moving the pivot axis 80 out of perpendicularalignment with the centroidal axis 54 and causing the segment 18 topivot about the centroidal axis 54.

The grab and drag system 20 (FIG. 6) includes an overhead frame assembly90, a two-axis gantry drive system 96 supported by the frame assembly90, and transfer system 98 supported by the drive system 96. The frameassembly 90 includes a pair of vertical members 92 that support ahorizontally-extending track member 94. The drive system 96 includes aplurality of servo motors and gear assemblies to move the transferassembly in a horizontal path 100 with respect to the extrudate support25, and to adjust the vertical location of the transfer system 98 withrespect to the extrudate support 25 along a vertical path 102. Adownwardly-extending support arm 106 supports the transfer system 98above the extrudate support 25. The transfer system 98 includes a frame108 fixedly connected to the support arm 106 and having a proximate end110, a distal end 112, and a pair of pad support portions 114 extendingoutwardly from a side of the frame 108 between the proximate end 110 andthe distal end 112. Each pad support 114 supports an extrudate segmentcontacting pad 116 therebelow. Each pad 116 is preferably constructed ofa flexibly resilient foam and is arcuately contoured. The arcuate shapeis preferably substantially similar to the arcuate shape of the outersurface of the extrudate segment 18. A pneumatic cylinder 118 is fixedlyconnected to the frame 108 beneath the proximate end 110 thereof. A rearpaddle 120 is connected to the operable end of the pneumatic cylinder118 and is adapted to contact an end of the extrudate segment 18 asdescribed below. The transfer system 98 further includes a compressedair system 122 having a plurality of switches 124 in operablecommunication with an air source such as a compressor 126 via aplurality of fluid lines 127. The air system 122 further includes aplurality of air lines 128 in fluid communication with heads 130extending through each pad support 114 of the frame 108. The purpose ofthe compressed air system is to enable the pads 116 to periodically be“blown out” to remove any debris that may accumulate on the pads duringperiods of transfer. Preferably, such blowing out of the pads 116 occurswhen the pads are not in contact with an extrudate segment 18, e.g.,when the pads are returning to the pick position to engage anotherextrudate segment 18.

In operation, the controller 132 adjusts the location and height of thetransfer system 98 with respect to the extrudate support 25 and beginsits horizontal movement. Once a gap is generated between extrudatesegment 18 and extrudate 14, the rear paddle 120 is positioned behind atrailing end 132 of the extrudate segment 18. The pneumatic cylinder 118is then utilized to help ensure containment of the extrudate segment 18with the transfer system 98 by moving the rear paddle 120 inward tocontact with the trailing end 132 of the extrudate segment 18. Theextrudate is transferred laterally via a frictional force between thepads 116 and the segment 18. The extrudate segment 18 is then moved in alinear path along the continuous air bearing 60 from the extrudatesupport 25, position A, to a dryer tray 134, position B, also includingan air bearing 135. The air bearing is shut off and the extrudatesegment 18 rests on the dryer tray 134. During the return of thetransfer system 98 to its original position, a short burst of air fromthe compressed air system 122 is provided through the pad supports 114and foam pads 116 to help eliminate any debris.

The wet log alignment camera system 23 (FIG. 7) includes a camera 140and an LED ring light 142 mounted within an housing 144, and a photo-eye146. The camera 140 takes an image of an end 148 of the extrudatesegment 18 resting on the dryer tray 134 as the extrudate segment 18passes by the photo-eye 146 and while the end 148 of the extrudatesegment 18 is illuminated by the LED ring light 142. The image asproduced, which includes a section of the end 148 that includes at leasttwenty-five walls 152, is communicated with a controller 150 thatcompared the measured image with a target range for alignment anddisplays relative information on a display monitor 149 where it isreviewed by the system operator. The controller 150 compares thealignment of the cell structure of the extrudate segment 18 to apredetermined range, as the alignment of the cell structure of eachextrudate segment 18 must be closely monitored to ensure properalignment so as to prevent deformation of the associated cell structureduring curing and/or firing. Specifically, the walls 152 cell structureof each segment 18 must be positioned at an angle relative to anabsolute vertical/horizontal to eliminate or reduce the amount ofdeformation, i.e., sagging, of the cell structure as the segment 18 iscured. Preferably, the alignment of the cell structure of the segment 18is kept within a range of ±3.0°, more preferably within a range of±2.8°, and most preferably within a range of ±1.8°. In a preferredembodiment, the wet log alignment camera system includes a second camerawhich takes an image of the end of extrudate 18 which is opposite theend the first camera images. In this way, the images from the two endscan be averaged by a computer, so that, in effect, the resultant imagethat is compared and/or displayed is an representation of the centerregion of the extrudate. Likewise, the difference between the imagesfrom the two ends can be used to report both the direction and themagnitude of the corkscrew of the extrudate 18, which can then be usedto define the corkscrew correction requirements via an associatedadjustment of the corkscrew correction roller system 16.

This information is relayed to the system operator via a color codedalignment matrix 154 on the display monitor 149. The alignment matrix154 includes a pair of vertical and horizontal alignment bars forreference, and an indicator bar 160 representing the measured readingfrom the extrudate segment 18 being monitored. The video monitor 149also displays a plot 162 of the previous nine readings plus the currentreading, thereby allowing the system operator to monitor any progressingtrends in the system. The plot 162 includes an outer pair of alignmentbars 163 representing the ±2.8° alignment range, and an inner pair ofalignment bars 165 representing the ±1.8° range. The system 10 is alsoconfigured to automatically divert those segments 18 failing to fallwithin the acceptable range to an auxiliary path 166 separate from themain conveyor line. Alternatively, the system 10 is configured torequire operator removal of the failing segment 18. A closed loopcontrol system is preferably included which allows for automaticadjustment of the automatic log alignment system 19 controller 68 basedon the results of the wet log alignment camera system 23 measurements.

The present inventive methods and associated apparatus disclosed hereinare highly consistent and repeatedly remove the inconsistenciesassociated with prior art methods and apparatus, reduce the deformationof the associated ceramic extrudates as manufactured via prior artsystems and methods, increase the precision of alignment prior to curingand/or firing the associated extrudates, reduce manufacturing cycletimes, and are particularly well adapted for the proposed use.

In the foregoing description, it will be readily appreciated by thoseskilled in the art that modifications may be made to the inventionwithout departing from the concepts disclosed herein. Such modificationsare to be considered as included in the following claims, unless theseclaims by their language expressly state otherwise.

1. An apparatus for orienting sections of a plasticized ceramicextrudate, comprising: a marking assembly for applying an orientationreference mark to a plasticized ceramic extrudate exiting an extrusiondie onto an extrudate support; at least one extrudate-contactingorientation control member for correcting the orientation of a cutsection of the extrudate on the extrudate support in response to avisual indicator of a misalignment of the reference mark; at least onegripping member adapted to laterally transfer the cut section of theextrudate along a linear path with respect to the extrudate supportwhile preventing any orientation change of the cut section of theextrudate support; and a visual inspection apparatus adapted to confirmthe orientation of the cut section of the extrudate on the extrudatesupport.
 2. The apparatus of claim 1, wherein the marking assemblycomprises an ink jet marker.
 3. The apparatus of claim 1, wherein theextrudate support comprises an air bearing.
 4. The apparatus of claim 1,further comprising: a corkscrew correction assembly adapted to correct acorkscrew deformation of the extrudate caused by the extrusion die. 5.The apparatus of claim 1, wherein the at least one gripping membercomprises at least one foam contact elements.
 6. The apparatus of claim1, wherein the visual inspection apparatus comprises a first camera forinspecting a first end of the extrudate and a second camera forinspecting a second end of the extrudate.
 7. The apparatus of claim 1,wherein the extrudate support comprises a first section for receivingthe extrudate exiting the extrusion die, and a second section separatedfrom the first section, wherein the gripping member is adapted tolaterally transfer the cut section of the extrudate along the extrudatesupport between the first section and the second section of theextrudate support. 8-13. (canceled)
 14. An apparatus for orientingsections of a plasticized ceramic extrudate, comprising: a markingassembly for applying an orientation reference mark to a plasticizedceramic extrudate exiting an extrusion die onto an extrudate support;and at least one extrudate-contacting orientation control member forcorrecting the orientation of a cut section of the extrudate on theextrudate support in response to a misalignment of the reference mark.15. The apparatus of claim 14, further comprising: a visual inspectionapparatus adapted to confirm the orientation of the cut section of theextrudate on the extrudate support.
 16. The apparatus of claim 14,wherein the marking apparatus comprises an ink jet marker.
 17. Anapparatus for correcting deformation of a plasticized ceramic extrudateexiting an extrusion die, comprising: a support frame; and at least oneextrudate-contacting deformable roller operably coupled to the supportframe and having an axis of rotation, wherein the axis of rotation ispivotable with respect to a movement of an extrudate exiting anextrusion die, and wherein the roller is adapted to contact theextrudate and correct a corkscrew deformation of the extrudate exitingthe extrusion die.
 18. The apparatus of claim 17, wherein the at leastone roller comprises a pair of spaced apart rollers.
 19. The apparatusof claim 17, wherein the at least one roller is vertically adjustable.